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Simulators >> Circuit Simulators >> Tline Diff. Insertion Loss Hspice simulation
https://designers-guide.org/forum/YaBB.pl?num=1173419631

Message started by thlcak on Mar 8^th, 2007, 9:53pm

Title: Tline Diff. Insertion Loss Hspice simulation
Post by thlcak on Mar 8^th, 2007, 9:53pm

Hi all,

I have this setup in hspice. The box is 4 port s-param of two 50 ohms traces
----------------------
inp -----| |---- outp
inn -----| |---- outn
----------------------

vin inp inn ac=1
rout outp outn 100

.ac dec 100 0 10g

When I plot 20*log10(vm(outp,outn)/vm(inp,inn)), the result looks bad.

I tried many other case like vinp inp 0 ac=1,0 and vinn inn 0 ac=1,180 and plot the differential insertion loss.

What did I do wrong?

Thanks,

Title: Re: Tline Diff. Insertion Loss Hspice simulation
Post by Geoffrey_Coram on Mar 9^th, 2007, 4:05am

thlcak wrote on Mar 8^th, 2007, 9:53pm:

.ac dec 100 0 10g

Surely this is a typo, you can't start at 0 on a logarithmic (dec 100) plot ...